Method of forming gelatin sheets



April 4, 1944. A. w. KATH 2,345,674

METHOD OF FORMING GELATINE SHEETS Original Filed Dec. so. 1938 s Sheets-Sheet 1 IN VEN TOR f7! 2227 /4. 4i jl/ J; kj W I A TTOR/VE K April 4, 1944. A. w. KATH 2,345,674

METHOD OF FORMING GELATINE SHEETS Original Filed Dec. 30, 1958 6 Sheets-Sheet 2 A TTORNE Y5.

April 4, 1944.

A. w. KATH 2,345,674

METHOD OF FORMING GELATINE SHEETS Original Filed Dec. 50, 1938 6 Sheets-Sheet 5 /N VEATOR A Thu-v12 ms.

April 4, 1944. A. w. KATH v ,345

- METHOD OF FORMING GELATINE SHEETS Original Filed Dec. 30, 1938 6 Sheets-Sheet 4 2,56 'i l l {2? w l 11v VENTOR A TTORNE Ya April 1944. A. w. KATH 2,345,674

METHOD OF FORMING GELATINE SHEETS Original Filed Dec. 30, 1938 6 Sheets-Sheet 5 kiw -2174"?" M;

E- K f W [NVENTOR A TTORNE V5- April 4, 1944. w H 2,345,674

METHOD OF FORMING GELATINE SHEETS Qriginal Filed Dec. 30, 1938 6 Sheets-Shea 6 I I I I I I I I IN VENTOR A T TORNE VS Patented Apr. 4, 1944 UNITED STATES PATENT OFFICE 2,345,674 r METHOD OF FORMING GELATIN sHEE'rs Alfred w. Kath, Detroit, Mich, assignor to A1- thur Colton Company, Detroit, Mich., a corporation of Michigan Original application December so, 1938, Serial No. 248,482. Divided and this application April 10, 1942, Serial No. 438,361

4 Claims.

This invention relates to a method of forming gelatin ribbons, sheets and leaves and is a division of my application for Letters Patent of the United the steps of applying liquid gelatin to a moving,

surface, maintaining said surface at a temperature above room temperature whereby to maintain the contacting surface of the gelatin in a tacky condition, and skin drying the opposite surface of such gelatin; the provision of a method of forming gelatin sheets as above described in which the moving surface comprises a drum, and a liquid above room temperature is circulated through the drum in contact with the peripheral wall thereof; the provirion of a method as above described inwhich air. is circulated over the exterior surface of the gelatinwhile in contact with the drum to effect the skin drying of such outer surface only; and the provision of a method as above described in which the gelatin is stripped from the drum and severed transversely of its length to form sheets, the severance being of an interrupted character whereby to provide spaced tongues of gelatin connecting adjacent sheets, the sheets are separated from one another whereby to stretch such tongues without rupturing them, and finally the tongues are severed, the sheets arranged in superposed pairs with the tacky surfaces thereof opposed and provided with a liquid fill between them, and such sheets as last arranged are then acted upon to form a plurality of liquid filled capsules;

The above being among the objects of the present invention, the same consists in certain novel steps of operation to be hereinafter described with reference to the accompanying drawings, and then claimed, having the above and other objects in view.

In the accompanying drawings which illustrate an illustrative embodiment of apparatus suit-.

Fig. 4 (sheet 4) is an enlarged fragmentary vertical sectional view taken on the line 4-4 of Fig. 3;

Fig.5 (sheet 5) is an enlarged vertical transverse sectional view taken on the line 5-5 of Fi 3;

Fig. 6 (sheet 3) is an enlarged fragmentary vertical view taken on the line 6-4 of Fig. 5 and illustrating ingreater detail the construction of the spreader box and spreader gate;

Fig. '7 (sheet 3) is an enlarged fragmentary, sectional view taken on the line 1-1 of Fig. 5;

Fig. 8 (sheet 4) is a more or less diagrammatic,

plan view taken on the line 8-8 of Fig. 4 and i1- lustrating in greater detail the variable drive mechanism for one of the machine units;

Fig. 9 (sheet 6) is a more or less diagrammatic fragmentary side elevational view taken on the line 9-9 of Fig. 4, illustrating the drive mechanism for one of the units of the machine;

Fig. 10 (sheet 6) is a fragmentary plan view taken on the line Ill--l0 of Fig. 9;

Fig. 11 (sheet 6) is an enlarged fragmentary sectional view taken on the line I l--l I ofrFi 10;

Fig. 12 is a fragmentary perspective view of one of the sheets or ribbons of gelatin such as is produced by the machine shown in the preceding views;

Fig. 13 (sheet 6) is a partially broken view of a gelatin capsule such as the sheet shown in Fig. 12 is employed to produce.

It is, of course, old practice to form gelatin sheets, ribbons or leaves by depositing a film of liquid gelatin upon the surface of a drum, there to be solidified, moved and out up into suitable sizes for use. Where such gelatin sheets or leaves are to be 'employedin the manufacture of liquid filled capsules, such as shown in Fig. 13 (conventionally accomplished by confining a suitable amount of oil or other medicinal agent between a pair of opposed gelatin sheets and then subjecting the filled sheets to a pressing operation between a pair of suitably formed dies), many problems and conditions arise which are not satisfactorily taken care of by heretofore existing equipment. For instance, in order to facilitate the handling of such sheetsln the manufacture of liquid filled capsules, it is necessary that that side of a sheet which comes into contact with the surfaces of the dies and of other objects from the time the sheets leave the forming drum until they have been formed into the capsules, be sufficiently hard or dry so as to prevent them from sticking to such surfaces. At the same time the opposite side of such sheet preferably is of a tacky nature so as to facilitate the welding of a pair of such sheets together about the diameter of each of the capsules formed therefrom and. to insure maintenance of a fluid tight joint at the line of connection between the two halves of the capsule. The machine designed in accordance with the present invention is capable of providing such gelatin ribbons, sheets or leaves at an unusually constant thickness and the finally diischarged product is that having the characteristics above noted rendering it particularly suitable for the production of liquid filled gelatin capsules. In the attainment of these results it will be appreciated that a machine designed in accordance with the present invention involves numerous novel and useful features necessary to the attainment of the above and other desirable results.

Referring to the accompanying drawings and particularly to Fig. 3 (sheet 3) a machine will be seen to include a gelatin spreader box indicated generally at 20 adapted to discharge liquid gelatin upon the surface of a roll or drum indicated generally at 22 rotating in the direction of the arrow, the thickness of the layer of gelatin thus-being deposited upon the surface of the drum 22 being controlled by means of a gate 24. The gelatin sheet. after making almost a complete turn with the drum 22, is stripp d off of the drum and'is led over a roll 26. A roll 28 positioned in spaced and parallel relation with respect to the roll 26 is connected thereto by means of a belt formed of a plurality of garter springs 30 trained around the peripheries of the rolls 28 and 28 and which belt forms a'means for conveying the gelatin strips from the roll 26 to the roll 28 and discharging it beyond the same. Where it is desired to cut the ribbon thus deliverecl from the drum 22 into a plurality of sheets or leaves of predetermined length. a rotary knife 32 is provided-in cooperationwith the roll 28 to eflect the desired result. The ribbons or sheets discharged from the roll 28 are preferably conducted to a delivery belt 34 trained over a pair of suitably spaced and parallel rolls 3B and 38 so as to deliver the ribbons or sheets to a desired point of discharge.

Referring now particularly to Figs. 1, 2, 3 and 5, it will be noted that the machine shown is provided with a supporting base consisting of a pair of spaced parallel channels 40 arranged :in back-to-back relationship and with the flanges thereof arranged horizontally. At one end of the channel 40 a cast supporting member 42 is rigidly fixed thereto for supporting the drum 22 and associated parts," and at the opposite end of the channels 40 a cast supporting member 44 is rigidly fixed thereto for supporting rolls 2B and 28, 36 and 38 and associated parts. Bars 45 may be provided for rigidly interconnecting the members 42 and 44, if desired.

Referring now particularly to Fig. (sheet 6) it will be noted that the member" at each side thereof is provided with a pillar 46 to the upper ends of each of which is suitably fixed a mem-' ber 48 which members non-rotatably support between them the hollow shaft 50. The drum 22 is rotatably supported upon the shaft 50 between the members 48 and its hubs are provided with bushings 52 in engagement with the shaft 50. The drum 22 is shown of built up construction including a circumferential wall 54 and separately formed end walls 56 suitably secured thereto as by welding. Hub sleeves 58 are welded into the end Walls 56 centrally thereof for reception of shaft 50 and rollers 52. Each end wall 56 has fixed thereto as by welding centrally thereof and on the outer side thereof a frustoconical skirt 60 which flares both axially and radially outwardly from their point of connection with such end walls. The small ends of the skirt 60 are of considerably larger diameter than the hub sleeves 58 and a plurality of openings 62 are drilled through each end wall 56 between the point of connection of the corresponding skirt member 60 and hub sleeve 58 therewith.

The holes 62 are for the discharge of water or other fluid medium from the interior of the drum 22 and for this purpose each of the pillars 46 on the inner side thereof is provided with a semicircular trough 64, the inner wall of which axially inwardly overlaps the lower outer edge of the corresponding skirt member 60 so as to insure water discharging from the skirt Ell being deposited in the corresponding trough 64. Each pillar 46 is provided with a cored passage 66 therein communicating with the bottom of the corresponding trough 64 and connected with suitable drain pipes 68 for conducting the water overflowing from the interior of the drum 22 through the holes 62 to a suitable point of deposit which will hereinafter be more fully explained. For the purpose of enabling the drum 22 to be substantially completely drained of water, a conventional screw plug 10 is preferably provided in one of the end walls 56 thereof adjacent the periphery thereof.

In order to lock the shaft 50 against rotation in the members 48, each of the members 48 is slotted radially adjacent one end thereof and provided with a cooperating bolt I2 for contracting the slotted end about the shaft 50 to thereby clamp it in position. As best illustrated in Fig. 5, one end of the shaft 50, shown as the lefthand end, is provided with a conventional screw plug 14 for closing such end of the shaft. The opposite end of the shaft is provided with a suit able pipe fitting 16 through which it is adapted to be connected to a suitable source of water or other liquid supply which flows into. the hollow interior of the shaft 50 and is discharged therefrom into the interior of the drum through a plurality of holes 18 extending through the walls of the shaft 52 between the hub shells 58. The fitting 16 preferably is provided with a thermometer, indicated generally at 19, for the purpose of enabling the temperature of the water flowing to the interior of the drum to be accurately checked.

In order to drive the drum 22, and as best illustrated in Figs. 2, 3, 4 and 5, an annular sprocket mounted upon a ring 82 is secured to the exterior face of one of the drum heads 56 in concentric relation therewith by means of bolts 84. A chain 86 trained over the sprocket 80 is also trained over a small sprocket 88 mounted upon and driven by a conventional form of gear reduction mechanism 90 suitably mounted upon the support 44. The gear reduction mechanism 90 is provided with a drive pulley 92 driven by means of a so-called V-belt 94 from a motor 96 (see Figs. 2 and 3). v

The spreader 'box 20, as best indicated in Figs. 1, 2 and 3, is positioned adjacent the highest point of the drum 22 and its open top is preferably provided with a strainer screen I00 therein (see Fig. 3) supported by a suitable frame I02 for the purpose of preventing any solid particles from becoming lodged in the spreader box. It will also be appreciated from an inspection of Figs. 1 and 2 that the spreader box 20 extends almost the full width of the drum 22. As best indicated in Figs. 3 and 6, the bottom walls of the gelatin containing recess in the spreader box 20 converge toward one another and in the direction of rotation of the drum 22 so as to provide a discharge opening or spout I04 terminating immediately above the upper surface of the drum 22 and extending across the same in axially parallel relation thereto. The walls of the spreader box 20 are hollow so as to form a chamber I06 completely surrounding the spreader box except at its top and this chamber serves to provide a water jacket for the spreader box whereby the contents may be maintained at a desired temperature. For the purpose of filling the chamber I06 with water or other suitable liquid, 9. pair of short pipes I08 are provided at the top of the spreader box and communicate with the chamber I06, the upper ends of the pipes I08 being provided with flared or funnel-like mouths IIO to facilitate the pouring of liquid thereinto. An electrical heating element H4 is projected through a side of the spreader box 20 into the liquid filled chamber I06 thereof and a thermostat I I2 similarly projected through a side of the spreader box and into the chamber I06. The thermostat H2 is provided with a connection I20 leading to an adjustable control box I I8 mounted on top of the-machine, as best indicated in Figs. 1 and 2. and the electricalheating element I I4 is provided with a lead II6 which receives its source of current from the control box II6 as governed thereby. A thermometer I2I (see Fig. 1) is preferably provided in connection with the spreader box 20 so as to enable the temperature of the liquid in the chamber I06'to be accurately checked. This temperature may be maintained at approximately 106 F. as a matter of illustration.

For the purpose of supporting the spreader box 20, a radially directed arm I22'is rigidly clamped to the axially outwardly projecting end of each member 48. As indicated in Fig. 3, the arms I22 areinclined upwardly and outwardly with respect to the corresponding end of the machine and at a point radially outwardly beyond the periphery of the drum 22 the arms I22 are rigidly interconnected by means of a cross-bar I24. Pivotally secured to the free end of each of the arms I22 is the forward end of a rearwardly extending arm I26. The arms I26 are laterally spaced from one another by a distance corresponding to the width of the spreader box 20 which is received between the rear ends of these arms and is rigidly fixed thereto. Each of the arms 'I26 adjacent the rear end thereof, and as best illustrated in Fig. 2, is provided with a downwardly projecting boss I28 carrying a short shaft or pin I30 in parallel relation with respect to the axis of the drum 22 and on the inner end of which a roller I32 is rotatably mounted, the rollers I32 bearing against the ax ally outer marginal edges of the peripheral surface of the drum 22 and thereby definitely locatingthe spreader box gate 24 with respect to the periphery of the drum 22. ,By this means the distance which the spreader box gate 24 is spaced from the peripheral surface of the drum 22, and consequently the thickness of the sheet or ribbon of gelatin to be formed is controlled from the surface of the drum 22. This obviates the disadvantage of conventional types of similar machines in which the spreader box and gate are supported from a fixed part of the machine and, accordingly, in which any variations in the peripheral surface of the cooperating drum will consequently cause variations in the thickness of the sheet or ribbon of gelatin being formed. In this respect it may be noted that it is practically impossible to maintain the surface of a drum such as 22 in accurately cy-.

lindrical conformation at all times due to the fact that changes in temperature, relieving of strains, etc., in the drum cause the drum to warp or spring at various points in its surface which inaccuracies result in conventional constructions in variations of sheet or ribbon thicknesses, but in the present case because of the manner in which the spreader box and gate are supported, these defects and particularly an out-of-round condition of the drum 22 can have little if any effect on the desired thickness of the final prod uct.

Means are provided, as best illustrated in Figs. 3, 4, 6 and 7, for mounting the spreader box gate 24 upon the spreader box 20 and enabling quick and accurate adjustment of the distance between the effective edge of the cutter bar gate and the'surface of the drum 22. To this end a pair of upwardly extending bars I40, preferably of rectangular section as shown, are secured .at their lower end to the spreader box gate 24 as by means of screws I42. The forward face of the spreader box, as best indicated in Fig. 5, is provided with a pair of laterally spaced guideways I44 for receiving the bars I40 and accurately guiding them for vertical movement therein. As best indicated in-Fig. 6, a pair of vertically spaced studs I46 are threaded into the spreader box 20 centrally of each guideway I44 and project outwardly therefrom through vertically elongated slots I48 provided in each arm I40 for reception thereof. Coil springs I60 surrounding each stud I46 outwardly of the corresponding bar I40 are maintained under compression between the corresponding bar I40 and a nut I52 threaded upon the outer end of each stud. By this means the bars I40 are resiliently maintained in contact with the cooperating guideways I44 and are permitted a limited amount of vertical movement, together with the spreader box gate 24, within the confines of the slots I48.

The forward face of the spreader box 20, as best indicated in Figs. 5 and 6, is also provided with a horizontal guideway I54 extending transversely across the tops of the guideways I44. Slidably received within the guideway I54 is a transversely slidable bar I56 lying inwardly or back of the upper ends of the bars I40. In line with each bar I40 the bar I56 is provided with an angularly extending slot I58 the walls of which serve as cam surfaces. Each guide bar I40 in line with its corresponding slot I58 is provided with a screw element I60 projecting therethrough and having on its inner side a cylindrical head I62 received in the corresponding slot I58 and of a diameter to be accurately received between the opposite side walls of suc slot. A nut I64 threaded upon the outer end of each screw element I60 serves to clamp the screw element I60 securely in place and against rotation on the bar member I40. One end of the bar member I56 is provided with a forwardly projecting lug I66, as best indicated n Fig. 5, and an axially fixed but rotatable screw I58 is mounted in an arm I10 secured to one end of the spreader box 20 and is threadably received in the lug I66. The screw 566 is provided w th an operating knob I 72 by means of which the screw I68 may be rotated and in rotating cause the bar I56 to be moved either to the right or left in the guideway I54 as viewed in Fig. 5. As will be appreciated, movement of the bar I56 to the right, as viewed in Fig. 5, cooperating through the screw element I60 and bars I40 will cause the spreader box gate 24 to move away from the surface of the drum 22 whereas rotation of the screw I68 to move the bar I56 to the left will cause the gate 24 to more closely appreach the surface of the drum 22, and because of the relationship of the parts the gate 24 will be maintained in parallel relation with respect to the surface of the drum 22 during such movement.

In order to effectively lock the gate 24 in itsvertically adjusted position the bar I56 centrally thereof is provided with a longitudinally extending slot I'I4 therethrough. As best indicated in Fig. 7, astud I16 in the outer wall of the spreader box 20 projects outwardly through the slot I14 and receives a wing nut I18 upon its outer end by the tightening of which longitudinal movement of the bar I56 may be effectively prevented thus to lock the gate 24 in its vertically adjusted position. 7

Again referring to Figs. 5 and 6 and particularly to Fig. -6, in order to provide an initial adjustment between the operative edge of the gate 24 and the surface of the drum 22 so as to insure equal spacing of the operative edge of the gate 24 with respectto the surface of the drum over its entire length, the cylindrical heads I62 on the screw elements I60 are located in eccentric relation with respect to the axis of the screw element I60 and the outer ends of the screw elements I60 are squared as at I 80 for reception of a wrench so as to enable them to be readily rotated. Accordingly, if it is desired to adjust one end of the gate 24 relative to the opposite end thereof and with respect to the surface of the drum 22, the corresponding nut I64 is loosened, a wrench is applied to the end I 80 of the screw element I60, and the element is 45 turned so as to raise or lower the corresponding bar I40 and consequently the corresponding end of the gate 24 the desired distance, by reason of the camming action of the head I62 in the cooperating slot It8, upon which the nut I84 is 50 again tightened to lock these parts in their thus adjusted position.

As previously mentioned, particularly where the sheets of gelatin formed by the machine are to be employed in the production of liquid filled 5 capsules, it is desirable that one surface of the sheet is provided with a more or less non-sticky skin and the opposite face of the sheets is maintained in more or less tacky condition. In order to provide one side of the sheet formed on the 00 drum 22 with such a non-sticking skin, means are provided for blowing air over the outer surface of the sheet formed on the drum 22 For this purpose a fan, indicated generally at I90, is mounted at the discharge end of the machine and, as best indicated in Fig. 1, is provided with an electric motor I92 fordriving the same. The inlet port I04 for the fan I80 (see Fig. 2) may be allowed to be open to the atmosphere in the room in which the machine .is located or it may be connected by suitable pipes (not shown) to any other suitable source of interior or outside air as may, be found most desirable. As best indicated :in Fig. 3, the discharge end of the fan I80 is conadjacent the bottom of the drum 22 where it connects with a substantially semi-cylindrical sheet metal deflector I98 which extends around the forward side of the drum 22 in slightly spaced relation with respect thereto. By the above described means a suitable volume of air may be directed over a relatively large exposed area of the outer surface of the gelatin sheet being formed on the drum 22 thereby to cause the same to be skin hardened on its exterior surface to the extent desired.

In order to maintain the opposite side of the gelatin sheet being formed on the drum 22 in a more or less tacky condition, the drum 22 is formed for the circulation of water through it as previously described and this water is maintained at a suitable temperature which in some cases at least may be in the neighborhood of 95 to 105 F. so as to prevent hardening of the inner surface of the sheet of gelatin and thus maintain it in the desired tacky condition. In order to maintain the water in the drum 22 at the desired temperature, a water tank 200 is mounted in the base of the machine between the channels 40, as'best indicated in Fig. 3. As indicated best in Figs. 1, 2 and 3, a water pump 202 secured upon the lower end of an electric motor 204 is suitably mounted at the discharge end of the machine by means of brackets 206. The intake side of the pump I02 is connected by means of a pipe 208 with the interior of the tank 200 and the discharge side of the pump 202 is connected by means of a pipe line 2I0 with the fitting I6 at one endof the drum shaft 50. The discharge pipes 68 for the drum 22 are connected into the tank 200 so as to discharge their contents thereinto. An electrical heating element 2I2 is pro iected through the rear end wall of the tank 200 into the water within the tank as best indi- 40 cated in Fig. 3 and a thermostat m is also projected through such wall into the interior of the tank as indicated in Fig. 1. Leads from the heating element, 2I2 and thermostat 2I4 extend to a control box 2I-6 mounted on top of the machine adjacent the control box I I8 previously described. The control box 2I0 is of a conventional adjustable type whereby the flow of electrical current to the heating element 2 I 2may be controlled under the influence of the thermostat 2 I4 to maintain the water in the tank 200 at the desired temperature. This water, in being circulated through the drum 22, will, of course, maintain the drum at the desired temperature necessary to maintain the inner surface of the gelatin sheet being formedon the drum in the desired tacky condition.

As perhaps best illustrated in Figs. 3 and 4, the support 44 for the rolls 26, 28 and 36 and other parts of the machine not heretofore spe-, cifically describedfirst extends upwardly from the channels 40 as laterally spaced posts 220 forming a passageway between them for the duct I96 and are joined thereabove to provide a horizontal relatively flat supporting surfac 222 bornected with a duct I96 which extends to a point the walls 224. Suitable adjustment is provided diameter of the pulley '252. ciated that in thusreducing the effective diamascaen for the spacing of the shafts 238 and 288 to adjust the tension of the belt 84. Corresponding ends of the shafts 228, 228 and286 each have fixed thereto a sprocket wheel 248, as best shown in Fig. 9, the sprocket wheels 248 being drivingly connected together for common movement by means of a driving chain 242 trained over them, idler sprockets 248 preferably being pro vided intermediate each pair of gears 248 so as to insure a greater degree of wrap around the intermediate gear 248 secured to the shaft 228 than would otherwise occur. a

, As indicated bestln Figs. 8 and 9, the chain 242 is trained over a driving sprocket 244 carried, by a conventional form of gear reduction mechanism 246, corresponding with the gear reduction 264 and the various sprockets 248. Thus by suitably operating the handle 218 thevarious rollers 26, 28 and 66 may be caused to increase or decrease in speed to obtain minute adjustments in speed of rotation thereof.

It might also be noted at this point that the mechanism for driving the drum 22, including i the gear reduction mechanism 88, belt 84 and motor 86 previously described, includes a substantially identical mechanism for varying the speed of the drum 22 with respect to its driv- -ing motor 86, including a controlhandle 65 so mechanism 68, previously described, and in turn driven by a pulley 248 which has'a cylindrical Outer surface. The pulley 248 i connected by a so-called V-belt 258 with the pulley 252,0n a driving motor 254, the belt 258 having a flat side for engagement with the pulley 248 and beveled sides for engagement with the beveled-sides of a longitudinally extending plate 256 carried by a bracket 258 formed upon the corresponding side pillar 228 of the support 44. The motor 254 is carried by a slide 268 longitudinally slidable upon the plate 256. The position of the slide 268 and consequently the motor 254 longitudinally of the plate 256 is controlled in the following manner:

A bar 262 is suitably secured to the motor 264 and extends therefrom to a point adiacentthe opposite end, of the plate 268 and at such end one,

side thereof is formedfto present arack 264. The rack 264 meshes with a pinion 266 fixed upon the vertical shaft of a suitable gear reduction mechanism 268 mounted upon the lower face of the plate 256 and having a suitable manually operable handle 218. From the above description it will be appreciated that by rotating the handle 218 the pinion 268 may be rotated and by rotat p the groove in thepulley 252. The gear reduction mechanism 246 and motor 254 are mounted upon that therelative speeds of both the drum 22 and the rolls 26, 28 and 36 may be accurately controlled to obtain any slight variation in their relative surface speed as may be required in .from the drum 22 over the roll 26. and to the roll 28, are relatively widely spaced axially of these rolls. In line with the desired location of eachof the belts 88, the rails 26 are peripherally grooved as indicated at 212 in Fig. 11, the depth of the grooves 212 being such that the outer surfaces of the garter springs 28 lie in substantially flush relationship withrespect to the peripheral surface of the rolls 26 and 26 ing will act through the rack 264 .to move the bar 262 and consequently the motor 254 longi tudinally ofthe plate 256 and relative to the gear reduction mechanism 246. i

As indicated best in Fig. 8, the pulley 252 is of a centrally split type, both halves of which are caused to turn with each other, but the outer half 212 of which is axially movable withrespect to the remaining half and is constantly urged When tension on the driving belt 258 is the motor 254 away from the gear reduction mechanism 246, the wedging effect of the belt 258 between the two halves of the pulley 252 cause separation of such two halves and permits the belt 258 to ride on an effectively smaller It will be appreeter'of thepul1ey 252, the ratio of movement between the motor 254 and the sprockfis 248 will be increased. In a similar manner, if the tension on the belt 258 is decreased as by suitably operatingthe handle'218 to draw the motor 254 closer to the gear reduction mechanism 246, the half 212 of the pulley 252 will be urged towards such other half by means ofla coil spring 214. increased as by operating the handle 218 to move by the spring 214 into closer relationship with respect to the fixed half of' the pulley and will cause the belt 258 to ride further out on the pulley 252, thus having the effect of increasing the diameter of the pulley.252 and to decrease the relative ratio of rotation between the motor parts, means are provided for heating the oil in when received in such grooves. Additionally, the surface of the roll 26 is provided with a plurality of preferably equally axially spaced smaller grooves 214, the main purpose of which is to reduce the area ofcontact between the roll 26 and the cooperating surface of the gelatin sheet or ribbon which passes over it. I'he reason for setting the garter springs 38 into, the surfaces of the rolls 26 and 28 is to provide a substantially laterally continuous support for the gelatin sheets or ribbons passing over them as well as, in the case of the roll 28, to permit employment of the particular type of severing mechanism to be later described where such mechanism is desired.

As indicated best in Figs. 3 and 4, an open top pan 216 is supported upon the surface v222 of the member 44 and is of such size and shape that the lower portions of the rolls 26, 28 and 66 are projected thereinto. The pan 216 is adapted to contain a quantity of liquid, preferably an oil and preferably a light mineral oil so that the rolls 26, 28 and 66 in dipping into such oil, as well as the garter springs 68 and belt 64, will be coated with the same so that the skinhardened side of the gelatin sheet or ribbon in contacting these rolls and belt, and later contacting other objects, as for instance forming dies,

will be relieved of any tendency to stick to these parts. In order that the bath of oil in the-pan 216 will not havea chilling effect on the gelatin sheet or ribbon passing over the rolls 26, 28 and belt 64 and so as to maintain the upper surface of the gelatin sheet or ribbon in a more or lesstacky state while passing overthese the pan 216. Forthis purpose the pan 216 is provided with a double bottom forming achamher 218 therein as best indicated in Figs. 1 and 2,

pwith the gear .298

A pipe 280 connectedinto the discharge pipe 2| for the pump 202 extends through the bottom of thepan 216 into the chamber 218, and a dis-- charge pipe 282 connectedwith the interior of the chamber 218 leads to the suction pipe 208 for the pump 202, so thatupon operation of the motor 204 and pump 202- the heated water orother liquid in the .tank 200 is not only caused to circulate through the drum 22, as previously described, but is also caused to circulate through "the chamber 218 in the bottom of the pan 216 and in-thismanner-maintain the. oil in the pan '216 at a desired temperature. In order to insure proper circulation of thi heating fluid through the chamber 218, a bafiie 284, as shown in" Fig. 3, is preferably positioned centrally of i the chamber 218 and extends from one end there-.

ofto a point adjacentthe opposite end thereof.

3; v The inlet pipe 280 connects into the chamber 218 Where it is desired to cut the gelatin ribbons formed on the drum 24 into sheets of predetermined length, the following mechanism is preferably provided. Upon the upper face of the side walls 224 of the support 44 a vertically extending standard 286 is rigidly fixed as by bolts or the like. 1

Each standard 288 isprovided with a vertically disposed slot 288 therethrough which forms a guideway for a 'journal box 290 received therein.

. Each journal box 290 is vertically adjustable in its corresponding guideway 288 by means of a rotatable screw 292 fixed against axial movement relative thereto and threaded upwardly through the corresponding standard v286 at the upper end of I the slot 288, a lock'nut 284 being provided for each same in vertically screw 292 in order to lock the adjusted position.

shaft'296having'fixed to one of its ends a gear ,m. 'The shaft 228 for the roll 28 is extended 1 axially on the same side of the machine as the gear 298 and has fixed theretoa gear 300 which meshes and consequently drives the shaft 296.

The knife blade or shear 32 is secured to the shaft 296 for equal rotation therewith between the standards 286 by means of a pair of semi-circular clampin members 302 having radially directed flanges '304 at the opposite margins thereof 1 1 through which bolts 306 are extended, the knife blade being interposed between opposed flanges 304 on'the opposite-members 302 and the corresponding'bolts 306 being extended through the knife blade 32 as indicated in Fig. 3. By this means the knife blade 32 is firmly clamped to the shaft 296 for equal rotation therewith.

The blade 32 is so adjusted with respect to the surface of the roll 28 that it substantially contacts the surface of the roll 28 each. time it is rotated "thereby to cause the ribbon or gelatin passing over the roll 28 to be transversely severed thereby. It

-will be noted that, because of the groove 212 formedin the surface of the roll 28 for reception 3 Y of the garter springs 80, the knife blade 32 will not sever that portion of the gelatin ribbon over th.

grooves 212, and consequently the ribbon will not ,be completely severed into sheets,-but each sheet thus severed will be connected to its adjacent sheet by a: plurality of relatively small tongues corresponding to the width and spacing of the v Rotatably mounted in the journal boxes 280 is a v grooves 212 as indicated at 301 in Fig. 12 in which the gelatin ribbon is indicated generally at 308 and the individual sheets at 309.;The purpose for providing this partial severance only of the "flOlll one another over the'area of severance between them. This may be desirable particularly in some cases in order to prevent any possible re-welding of the severed edges ofthe sheets 309 once they have been severed and also to facilitate the tearing of one sheet from another at the discharge end of the machine.

It will be appreciated that the surface speed of the belt 34 may be made slightly greater than the surface speeds of the rolls 26 and 28 either by making the roll 36 of slightly larger diameter than the rolls 26 and 28, or else by making the sprocket 240 of the shaft 236 slightly smaller indiameter than the sprockets 240 on the shafts 228 and 228.

It will'also' be appreciated that the length of the sheets-309 severed from the gelatin ribbon 308 may be'varied as desired by varying the ratio between the gears 288 and 300 so as to drive the shaft 296'and consequently the knife 32 at a multiple or division, orpart thereof, of the speed of rotation-of the rolls 26 and 28.

- Switches indicated at 3I0 in Figs. 1, 2 and 3. for controlling energization of the various motors and electrical heating elements provided in the machine may be grouped in a suitable mounting and supported on top of the standards 286 as indicated, if desired, the particular mounting thus shown for the switches also serving as a support for the control boxes H8 and H6 for the electrical heating element H2 and 2I2, respectively. It will also be appreciated that suitable shields such as 1H2v may be provided over certain driving parts of the machine in order to protect the operators of the machine from possible injury by contact therewith.

Formal changes maybe made in the specific embodimentiof the invention'described without departing from the spirit and substance of the invention, the scopeof which is commensurate with the appended claims.

What is claimed is:

1. In the manufacture of gelatin sheets by spreading athin layer of heated gelatin upon the surface of a revolvingdrum, the steps of cooling and drying the outer exposedsurface of said layer, by forcefully .flowing air at a temperature not substantially greater. than atmospheri temperature over said outer surface, and

simul aneously maintaining the surface of said of said strip while'cn said member by flowing air at a lower temperature than said gelatin thereover and maintaining the opposite face therof at an elevated temperature whereby to harden said exposed face and maintain said opposite face in tacky condition, stripping said strip from said member, partially severing said strip at predetermined intervals in the length thereof to form connected sheets, and placing said strip under longitudinal stress'after said partial severance whereby to stretch the unsevered portions between said sheets and separate saidsheets transversely of the lines of partial severance between them. a

3. In the manufacture of gelatin sheets by discharging a layer of heated 'gelatin upon a moving surface, the steps of cooling one surface of said layer by flowing air at a lower temperature than said gelatin thereover and maintaining the opposlte surface thereof at a temperature materlally above room temperature, whereby the resulting sheet will have one surface relatively hard and the opposite surface relatively tacky, stripping said layer from said drum, acting upon said layer to completely sever it at intervals onLv over the width thereof at predetermined points in the length thereof whereby to form connected sheets therefrom, and simultaneously with said severing placing the connected portions between the sheet being severed and the unsevered portion of the layer under tension longitudinally of said layer whereby to stretch said connected portions.

4. In the manufacture of gelatin sheets by discharging a layer of heated gelatin upon a moving surface, the steps of cooling one surface of said layer by flowing air at a lower temperature than said gelatin thereover'and maintaining the opposite surface thereof at a temperature materially above room temperature, whereby the resulting sheet will have one surface relatively hard and the opposite surface relatively tacky, stripping said layer from said drum, maintaining said layer at a temperature above room temperature whereby to maintain said opposite surface in its tacky condition and acting upon said layer to completely sever it at intervals only over the width thereof at predetermined points in the length thereof whereby to form connected sheets therefrom, and simultaneously with said severing placing the connected portions between the sheet being severed and the unsevered portion of the layer under tension longitudinally of said layer wherebyto stretch said connected portions.

ALFRED W. KATH. 

